334 AMERICAN HYMENOPTERA. 



appears to be confined mainly to the mountain chains and 

 it must be considered a Boreal Region (possibly also a some- 

 what Transition Zone) form. It probably is not to be found 

 much farther south or east than the records above given. 

 How far north does it range and how far east in Canada ? 

 It seems to be rare in Alaska and to increase in abundance 

 southward, reaching its maximum through western Mon- 

 tana. It seems to be rather common on the higher lands of 

 Colorado. 



This species has by far its closest allies in fernaldi, ter- 

 nariiis, vosnesens kit and huntii. Of these, htt7itii is apparently 

 the nearest, and they often resemble each other not a little 

 in coloration, but they can be instantly separated by the dif- 

 ference in form of the posterior border of the black interalar 

 band and by the striking difference in the color of the cor- 

 bicular fringe. B. ternarius, with its structurally different 

 male antennas, is evidently much less closely allied than is 

 vosnesenskii. It is interesting to note that, of these five closely 

 allied forms, the four with yellow faces are also structurally 

 the most alike, though differing otherwise remarkably in 

 coloration. 



This species and rufocinctus have probably caused the 

 workers on the Bombidae of North America more trouble 

 than most others. 



I have seen queens and males of this species taken in 

 coitu. 



Boniljus (Bonibus) melanopygus Nyl. 

 Bombus melatiopyge Nylander, Notis. Saellsk. faun, and fl. Fenn. 



Forh., I, 1848 (adnot.), 236, cf . 

 ? " ornatus Smith, Catal. Hym. Brit. Mus., II, 1854, p. 398, n. 



52, 9 cf. 

 ?* " tnenestriesii Radoszkowski, Bull. Soc. Natural. Moscou, 

 XXXII, P. 4, 1859, p. 483, n. 6, 9 cf ; T. 5, 

 F. 6. 

 " melanopyge Cresson, Proc. Ent. Soc. Phila., II, 1863, p. 103, 

 n. 31. 

 lacustris Cresson, Proc. Ent. Soc. Phila., II, 1863, p. 103, n. 

 32. 

 " melanopyge Cresson, Trans. Amer. Ent. Soc, VII, 1879, p. 

 231. (Catal.) 



